1. Field of the Invention
The present invention relates to a method of grinding a wafer by which the back-side surface of a wafer such as a semiconductor wafer is ground.
2. Description of the Related Art
In the semiconductor device manufacturing process, a semiconductor wafer provided with a plurality of circuits such as ICs and LSIs is made to have a predetermined thickness by grinding the back-side surface thereof using a grinding apparatus, before being divided into individual chips. The grinding apparatus includes a chuck table for holding the wafer, and a grinding means for grinding the wafer held on the chuck table. In order to grind the back-side surface of the wafer efficiently, a grinding apparatus is generally used which includes a rough grinding means having a rough grinding wheel and a finish grinding means having a finish grinding wheel (refer to, for example, Japanese Patent Laid-open No. 2001-1261).
In grinding a wafer by use of the just-mentioned grinding apparatus having a rough grinding means and a finish grinding means, the wafer held on the chuck table is subjected to rough grinding by the rough grinding means so as to leave a finishing margin, and the wafer having thus undergone the rough grinding is subjected to finish grinding by the finish grinding means so as to obtain a predetermined thickness.
When the wafer ground by the rough grinding means is ground by the finish grinding means, the minute grain diameter of the abrasive grains of the finish grinding stone constituting the finish grinding wheel of the finish grinding means may result in that the so-called bite into the wafer is weak so that surface burning occurs. Besides, the pressing force may be increased attendant on the grinding feed, leading to lowered quality of the wafer.